Nitrous oxide is released to the atmosphere when fertilizer decomposes in the

Nitrous oxide is released to the atmosphere when

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Nitrous oxide is released to the atmosphere when fertilizer decomposes in the soil. (Some of the nitrogen enters the air as nitrous oxide.) Nitrous oxide also is produced by the high temperature combustion of fossil fuels.
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Increases of Methane and Nitrous Oxide in the Atmosphere Increases of Methane and Nitrous Oxide in the atmosphere reflect the growth in human populations, and the affluence of many populations. Affluent populations favor a diet of animals and animal products in contrast to plants . Worldwide we feed about twice as much grain to domesticated animals as we ingest directly ourselves.
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CFCs (Chlorofluorocarbons) CFCs are broken down in the stratosphere, and the chlorine released breaks down the stratospheric ozone layer. But CFCs may take decades, or even a century to travel from the troposphere to the stratosphere. CFCs that remain in the lower atmosphere (troposphere) are powerful greenhouse gases . They are very effective, because they absorb and reradiate large amounts of infrared wavelengths missed by CO 2 and H 2 O in the lower troposphere. One molecule of CFC 11 or CFC 12 can trap as much heat as 10,000 molecules of CO 2 . CFCs are responsible for about 25% of the enhanced greenhouse effect. CFCs have an atmospheric lifetime of 65 – 130 years.
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Greenhouse Gas Mitigation Methane would be the easiest greenhouse gas to control, because its residence time in the atmosphere is only 10 years. Its concentration in the atmosphere would diminish quickly as a response to a reduction in production. A cut of 10 – 20% in methane emissions would halt the increase of methane in the atmosphere (EPA) . Better feed and nutrition for ruminant animals (cattle, sheep, goats, and camels) would decrease their methane gas production considerably. They currently eat vegetation low in nutrition, but high in fiber, and consequently generate considerable methane. Reductions in methane would also be accompanied by increases in productivity of milk and meat producing animals. Reductions in methane emissions from coal beds and landfills can be done at a profit.
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CO 2 Mitigation It would take a reduction of 50 – 80% in CO 2 emissions before a stabilization in CO 2 levels would occur. CFC Mitigation A reduction of 100% in CFC emissions is necessary to stabilize atmospheric CFC levels.
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Positive Feedbacks “The warmer it gets, the faster it gets warmer.” (These feedbacks reinforce, amplify, and accelerate the initial change.) 1) Increasing amounts of water vapor in the atmosphere. 2) Decreasing perennial sea ice in the Arctic Sea. 3) Deforestation of Tropical Rainforests 4) Release of methane hydrates a) from continental shelves b) from high latitude soils 5) West Antarctic Ice Sheet 6) Ocean Water Warming 7) Wildfire Climate Feedback
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1) Increasing amounts of water vapor in the atmosphere: As global temperatures increase, evaporation from global oceans increases. Higher air and water temperatures increase the rate that water evaporates into the atmosphere . With a one degree Celsius (C) increase in temperature, the atmosphere holds 7% more moisture.
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